June, 1911.] Severin-Severin : Habits of Belostoma and Nepa. 99 



HABITS OF BELOSTOMA (=ZAITHA) FLUMINEUM 



SAY AND NEPA APICULATA UHLER, WITH 



OBSERVATIONS ON OTHER CLOSELY 



RELATED AQUATIC HEMIPTERA. 



By Henry H. P. Severin, Ph.D. 

 Professor of Entomology, College of Hawaii. 



AND Harry C. Severin, M.A. 



Professor of Entomology, South Dakota State College of Agriculture 

 AND Mechanic Arts. 



Collection of Material. — Belostoma fluminemn inhabits ponds or 

 sluggish streams. While specimens were often captured, in our 

 experience, in shallow water a few inches in depth, they were fre- 

 quently taken in deeper waters. During early autumn before the 

 leaves had fallen, this aquatic hemipteron was often obtained by 

 raking out floating masses of vegetation from the water ; it was also 

 stream or pond and turned over on the shore. Later in fall, speci- 

 found below the thick scum of surface algae which were taken from a 

 mens were captured by scooping up with a water-net the leaves which 

 were floating on, or had sunk below the surface of the water. After 

 the water was covered with a thin coating of ice, these insects were 

 taken by pulling up with a rake the sediment on the bottom of the 

 stream or pond, or the roots of grass and mud along the bank. Some 

 of the bugs, which happened to escape by this method, were caught 

 by making a rapid current in the water with a net and then suddenly 

 reversing the movements of the net by scooping against the current. 

 A large number of individuals, when taken out of the water by any 

 of these methods, would not feign death, but would right themselves, 

 if they happened to drop on their backs, and scramble eagerly to 

 escape. Many, however, were found while feigning death, although 

 often with great difficulty, either on account of their rather close 

 resemblance in color to the leaves that had fallen into the water or 

 to the mud which often coated the insects. 



As Bueno (7, p. 138) has observed, Nepa apiculata "is found in 

 quite shallow water, not much over two or three inches deep, con- 

 cealed in the mud, or in situations where grasses grow out of the 



